Add the initial build task code
Updated code generator to use Java tool and support ANTLR 4 options
Add the CSharpTool extension of Tool to get access to generated file names during the code generation process
Generate shaded jar for the C# target
Update build message processing for the ANTLR 4 message formatting
Handle exceptions in message processing
Parse generated files messages
Fix working directory
Sign the Antlr4BuildTasks assembly
Merge branch 'build'
Fix build warnings
Added copyright header
Remove automatic left factoring declaration from Java.g4 since the processing is currently very slow
Copy Antlr4.targets to the output directory
Add code generation binaries and generate code for Java.g4 during the build